Eyewear for ballistic and light protection

ABSTRACT

The present invention provides eye protection systems. The eye protection systems include a lens capable of being mounted in and being interchangeable between a plurality of different lens-mounting platforms. These platforms may include spectacles or goggles with release mechanisms, which permit the lens to be removed while providing full ballistic protection when installed in the platform. The lens of the present invention protects against a plurality of threats including spectrums of light, such as sun light, ultraviolet light, or laser light, wind, dust, projectiles, etc. The lens may include a laminate structure, which protects sensitive technologies from exposure to environmental conditions, such as chemicals, weather, etc.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of co-pending application Ser. No.10/215,717 filed on Aug. 9, 2002.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to protective eyewear and moreparticularly to a multiple threat eye protection system, which includesan easily removable lens that is transferable between multiplelens-retaining platforms.

2. Description of the Related Art

Eye protection systems have a plurality of applications. Eye protectionsystems may be employed as sports equipment, e.g., ski goggles, asprotection for work activities, as protection for military applicationsor many other applications. Typical eye protection systems include azero-power plano lens, which is employed for wind, dust and debrisprotection, whereas military eye protection systems typically requireadditional protection from threats such as high speed ballistics andultra-violet light. While these lenses may be removed, they oftenrequire tools and the disassembly of multiple parts to do so. It wouldbe advantageous to provide a lens, which is easily removable without theuse of tools from one or more retaining platforms, such as a goggle orspectacle.

Eye protection can be provided on a plurality of different platforms.For example, goggles protect against dust and wind while spectacles arepreferred for sunlight protection. Each of these platforms isconstrained by different requirements and different physical attributes.For example, goggles tend to sit further from the face of a user thanspectacles. Additional differences between these platforms include thepantoscopic tilt angle of the lens relative to the face of the user andthe overall size of the lens to provide proper coverage of the user'seyes.

The production of military eyewear tends to be material and timeintensive. In particular, lens designs which include protection frommultiple threats typically undergo many processing steps, which affecttheir yield and therefore cost. It would be advantageous to provide alens system, which is interchangeable between different lens retainingplatforms, which addresses the difficulties in employing the same lensfor multiple platforms. Such a lens system would reduce cost bypermitting a single lens to be employed on several platforms.

Lenses for military applications typically include coatings or layersformed thereon. Despite providing ballistic protection, these lensescannot in many cases provide adequate scratch resistance, and lightprotection layers are vulnerable to scratches and, if scratched, maycompromise their light protection effectiveness. For example, wherelaser or other light protection is provided, scratches in the protectivecoating could render the lens useless for light protection applications.The lens must therefore be replaced. It would be advantageous to improvescratch resistance of the lenses, which are designed to protect againstlight threats, e.g., laser light.

Therefore a need exists for lens retaining platforms, which provide aneasy and quick release mechanism for removing a lens and accommodatelenses of different thicknesses and which can be interchanged betweenthe platforms. A further need exists for a lens system, which protectsagainst multiple threats and provides a structure, which protectsoptical technologies from scratch or other damage.

SUMMARY OF THE INVENTION

The present invention provides eye protection systems. The eyeprotection systems include a lens capable of being mounted in and beinginterchangeable between a plurality of different lens-mountingplatforms. These platforms may include spectacles or goggles withrelease mechanisms, which permit the lens to be removed while providingfull ballistic protection when installed in the platform. The lens ofthe present invention protects against a plurality of threats includingspectrums of light, such as sun light, ultraviolet light, or laserlight, wind, dust, projectiles, etc. The lens may include a laminatestructure, which protects sensitive technologies from exposure toenvironmental conditions, such as chemicals, weather, etc.

The present invention includes an eye protection system having a lensfor protecting both eyes of a user. The lens is interchangeable betweenmultiple platforms. The platforms include at least one of a gogglesassembly and a spectacles assembly, which detachably receive the lensand hold the lens in a position on a face of the user by securing thelens about its periphery.

In another embodiment, an eye protection system includes a frame havinga recess formed therein, and an elastomeric subframe attached to theframe and lining surfaces of the recess. The recess is configured toreceive a lens such that the lens, when installed, remains in contactwith the subframe. Tabs are disposed at a periphery of the recess on afirst side of the frame to provide a gap between the subframe and thetab, which permit the lens to fit in the gap. A release mechanism isdisposed at a periphery of the recess on a second side opposite thefirst side of the frame. The release mechanism secures the lens whenplaced in a first position.

In another embodiment, the eye protection system includes a unitary lenshaving two lobes and a centrally disposed arch adapted for a nose of auser. A brow bar has opposing extensions extending therefrom, theextensions capture a portion of the lens, which opposes the brow bar. Asupport portion is included for capturing the lens, and the supportportion is detachably connected to the arch of the lens and extends overthe brow bar to secure the lens to the brow bar. Arms are pivotallyconnected to the brow bar for securing the lens on a user.

The present invention includes a lens system for protection againstlight and ballistics, which includes a first lens having a convexsurface. A hologram is adhered to the convex surface. A second lensincludes a concave surface. A dielectric stack is formed on the concavesurface. An index-matching adhesive is provided for connecting theconvex surface with the hologram to the concave surface with thedielectric stack.

Other lens-retaining platforms and lens structures are contemplated bythe present invention. The illustrative embodiments of the presentinvention should not be construed as limiting the present invention aspresented in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The advantages, nature, and various additional features of the inventionwill appear more fully upon consideration of the illustrativeembodiments now to be described in detail in connection withaccompanying drawings. In the drawings wherein like reference numeraldenote similar components throughout the views:

FIG. 1 is a perspective view of an eye protection system in accordancewith one goggles embodiment of the present invention;

FIGS. 2A and 2B are schematic cross-sectional views showing theinstallation of a lens in accordance with one embodiment of the presentinvention;

FIGS. 3A and 3B are elevation views of a release mechanism in open andclosed states, respectively, in accordance with one embodiment of thepresent invention;

FIGS. 4A and 4B are a front and side view, respectively, of a multiplethreat lens for the eye protection systems of the present invention;

FIG. 4C is a cross-sectional view through the lens of FIG. 4A and aprescription lens carrier in accordance with one illustrative embodimentof the present invention;

FIG. 5 is a schematic cross-sectional view of a laminate lens assemblyin accordance with the present invention;

FIG. 6A is a perspective view of an eye protection system in accordancewith another spectacles embodiment of the present invention;

FIGS. 6B and 6C are magnified schematic cross-sectional views showingthe installation of a lens in the spectacles of FIG. 6A which provides atorsional preload in accordance with one embodiment of the presentinvention;

FIG. 7 is a perspective view of another spectacles eye protection systemwith a support removed to show how a lens is secured to the frame of thespectacles in accordance with yet another embodiment of the presentinvention;

FIGS. 8A and 8B are schematic views showing attachment schemes for theprescription lens carrier of FIG. 9 for the eye protection systems ofthe present invention;

FIG. 9 is a perspective view of a prescription lens carrier inaccordance with another embodiment of the present invention; and

FIG. 10 is a schematic perspective view showing a lens system having thecapability of being interchangeable between goggles and spectacles inaccordance with the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention provides an eye protection system, preferably amilitary eye protection system, which provides a lens, which isinterchangeable between lens-retaining platforms. For example, a lensmay be employed with a goggles system, then removed from the gogglesystem and inserted into a spectacle system. The present inventionfeatures custom designed quick release mechanisms on each lens-retainingplatform, which make the lens easily removable and installable withoutthe use of tools. The lens-retaining platforms of the present inventionprovide for anthropometric adjustments to individual users. The lenssystems of the present invention provide the capability to easilyreplace the lenses. Prior art systems required time (e.g., about 10minutes), tools (e.g., a screwdriver) and manual dexterity to replacethe lens. The present invention provides the capability of easilyremoving and replacing lenses. In addition, the lenses of the presentinvention are interchangeable between different lens mounting platforms.Despite the removeablity and interchangeability of the lenses of thepresent invention, each lens provides full ballistic protection whenproperly installed on the various platforms.

Referring now in specific detail to the drawings in which like referencenumerals identify similar or identical elements throughout the severalviews, and initially to FIG. 1, an isometric view of one embodiment ofan eye protection system 10 in accordance with the present invention isshown. System 10 includes a resilient frame 12 preferably formed using apolymeric material, such as, a resilient plastic, for example,polycarbonate, polyamide, etc. Frame 12 supports an elastomericsub-frame 14. Sub-frame 14 provides many advantageous features to system10. These features include, inter alia, providing a seal against theface of a user (in region 14 a), providing a comfortable interface forthe user (in region 14 a), providing a seal for a lens (in region 14 b)and permitting facial movement (anthropometric adjustments) without lensmovement relative to the eyes of the user (in regions 14 c).

Frame 12 preferably receives portions of sub-frame 14 at or nearattachment points for an adjustable strap 16. In this way, flexibilityis provided in system 10 wherein the frame 12 and sub-frame 14 arepermitted to flex with minimal impact displacement of the periphery of alens 20 relative to frame 12 and sub-frame 14. Sub-frame 14 includes aportion 18, which extends over a portion (not shown) of frame 12. A lip22 extends from portion 18 to provide a gasket against which lens 20forms a seal when installed. Sub-frame 14 includes corrugations 24,which provide additional deflection capability of sub-frame 14 whilemaintaining frame 12 and lens 20 in place. Frame 12 includes vent holes26 to permit fresh air to enter and to permit humidity to escape from aspace created between a user and lens 20 when system 10 is worn.Sub-frame 14 includes vent holes 28 in communication with holes 26 toprovide an air path between the space between the user and lens 20 andthe ambient environment. Vent holes 26 and 28 may be placed at otherlocations on system in addition to or instead of the locations shown. Afilter or screen may be provided over holes 28 or holes 26 to preventparticles, dust, etc. from entering the space between the user and lens20. In one embodiment, a screen (not shown) is adhesively bonded to theelastomeric material of sub-frame 14. In other embodiments, the screensare attached to sub-frame 14 via placement of the screens onto a polymerframe and then attaching this frame to sub-frame 14.

System 10 includes release mechanisms 32 preferably located at a lowerportion of system 10. Release mechanism 32 works in conjunction withtabs 34 which are formed in frame 12 on an opposing side of lens recess36 relative to mechanisms 32. An adjustable head/helmet strap 45 mayalso be included. Strap 16 may include additional features to adjust thecircumference of strap 16, which are needed for accommodating differenthead sizes, helmet sizes, and helmet shapes. This strap 16 can be wornover or under different helmet systems depending upon the need. Anotherfunction of vertical strap 45 includes keeping the strap in place whenplacing it on the helmet and then may be moved toward the face of a userto secure strap 16 in position.

A support 35 is included to provide additional support to frame 12. Inaddition, support 35 contributes to the structural integrity of system10. Support 35 may be attached to portions of frame by employingfasteners such as screws or rivets, for example.

Referring to FIGS. 2A and 2B, installation of a lens 20 is schematicallyshown in a cross-sectional view in accordance with an illustrativeembodiment of the present invention. Lens 20 (illustratively shown asstraight instead of curved) is mounted within recess 36 by introducing atop edge 40 of lens 20 at an angle into recess 36. Top edge 40 is heldin the front by tabs 34 and in the back by sub-frame 14. While releasemechanism 32 is retracted, a bottom portion 42 of lens 20 is insertedinto recess 36 in the direction of arrow “A”. Release mechanism 32 isadvanced in the direction of arrow “B” to hold lens 20 in place andapply a preload against lens 20 to form a seal against sub-frame 14which lines recess 36. Tabs 34 and release mechanisms 32 areadvantageously located at the periphery of lens 20. In this way, fieldof view obstruction is minimized.

Referring to FIGS. 3A and 3B, release mechanism 32 includes a pluralityof useful features. Release mechanism 32 includes a lever arm 44, whichis pivotally attached to frame 14. A peg 46 (shown in phantom lines) ispreferably integrally formed in frame 14. Lever arm 44 includes a holeformed therein, which receives peg 46. A cover portion 48 fits overlever arm 44 and engages peg 46 to prevent lever arm 44 from beingdislodged from peg 46. Lever arm 44 includes an integrally formed handle49 on a first end portion and an engagement portion 50 on a second endportion. When lever arm 44 is rotated to a first position, engagementportion 50 is retracted into cover portion 48 clearing the lowerperiphery of lens 20 as shown in FIG. 2A, permitting lens 20 to pivotforward out of recess 36 at that location. When lever arm 44 is rotatedto a second position, engagement portion 50 is advanced past coverportion 48 over a portion of lens 20 permitting lens 20 to be retainedand preloaded in recess 36 at that location. When lever arm 44 is in itssecond position (to maintain lens 20 in recess 36), a protrusion (notshown) formed on lever arm 44 engages a hole 54 formed in frame 12. Inthis way, lever arm 44 is secured to prevent lever arm 44 from rotatingand thereby releasing lens 20 from its secured position. A handle 52 isprovided so that a user can move lever arm 44 between positions withoutthe use of tools and can remove the lens 20 from the goggle/spectaclewhile wearing gloves. Advantageously, the lens 20 can be changed withoutdoffing and then donning the goggle.

Recess 36 and sub-frame 14 of system 10 provide sufficient tolerance tosupport a wide range of lens thicknesses. In one embodiment, theelastomeric material of sub-frame 14 in recess 36 includes a springconstant (elastic or Young's modulus) sufficient to accommodate a rangeof thicknesses, for example, of between about 0.5 mm and about 6 mm.Lever arm 44 of release mechanism 32 provides sufficient rigidity tosupport the compressive forces resulting from the deflection ofsub-frame 14. This feature of the present invention substantiallyimproves the capabilities and interchangeability of lens within system10.

The method for securing and releasing lens 20 provided in system 10permits easy installation and removal of lens 20 without the use oftools. This permits easy replacement of lens 20 to adapt system 10 for anew threat or to simply replace the lens 20 with a new lens. It is to beunderstood that other types and kinds of release mechanisms may beemployed in accordance with the present invention. These may include,among other things, biased lever arms, snaps, fasteners or othersecuring devices located at the periphery of the lens to ensure the lensis retained properly in its platform.

Referring to FIGS. 4A, 4B and 5, lens 20, in accordance with the presentinvention, provides ballistic protection for a user. As such, lens 20includes a transparent or semi-transparent resilient material. In apreferred embodiment, a polycarbonate material is employed for lens 20.Lens 20 preferably includes a thickness “t” of between about 0.5 mm toabout 6 mm. Lens 20 includes a plurality of different types, each typefor addressing a different threat or plurality of threats. For example,one lens type may include a clear polycarbonate designed for ballisticprotection while another may include additional dyes or additionallayers for light protection.

Dyes may be introduced into or on the polycarbonate material for ultraviolet radiation protection, sun light protection, visible lightprotection, infrared protection, etc. Dielectric stacks may be includedin lens 20 to provide protection from predetermined wavelengths orspectrums of light. In addition, holograms or other optical features maybe included. Different combinations of all of the above-mentionedfeatures are also contemplated for lens 20.

Lens 20 includes a compound curvature adapted to provide a zero powerplano lens with minimal distortion. The lens 20 may also be providedwith a spherical curvature on both inner and outer surfaces. Lens 20 mayalso include toric and/or aspherical curvatures.

Referring to FIG. 4C, the selection of the proper lens curvature was oneimportant aspect of the present invention. To address limitationsdictated by field of view requirements and the desire to maintain lenscompatibility between the goggle and spectacle, the present inventionprovides a useful lens design, which is interchangeable betweenplatforms and protects against multiple threats without interfering withthe field of view of the user. Goggles tend to have flatter lenscurvatures, meaning their radius of curvature is greater. This is due tothe way a goggle fits on the face. The goggles normally contact on topof the brow and around the cheekbones to fit the anthropometric featuresof a human. Therefore, a flatter lens is needed for goggles. Sunglassesmove to a smaller radius to achieve the wrap around effect found inpopular sports sunglass designs. Sunglasses or spectacles need to employas low of a radius of curvature as possible, while continuing to providenecessary form, fit and function. The unlikely combination of thesefeatures was advantageously achieved in accordance with the presentinvention. In accordance with one aspect of the present invention, thesame lens employed for a spectacle can now be employed in goggleswithout reducing the effectiveness of the goggles.

For the best performance of the present invention, faceform angle andfield of view parameters were carefully addressed and selected. Theseparameters (i.e., faceform angle and field of view) were considered foreach system alone and each system when worn with a prescription lenscarrier 300 (results in reduced field of view). Field of viewrequirements for the lens systems of the present invention includedmeasurements at each of the major meridians around the lens: superior,inferior, temporal and nasal directions (measured at 45 degreeincrements). The field of view is a result of the trim size of the lens,the amount of eye relief (for the pupil to the inner surface of theplastic lens), and the lens curvature. Other requirements on theprescription lens carrier 300 included faceform angle, measured from thecenter of the lens to the point at which the lens carrier hits the innersurface of the plastic lens. FIG. 4C shows dimensions of one preferredembodiment and is provided for illustrative purposes. Other dimensionsmay also be employed in accordance with the present invention.

Lens 20 preferably does not exceed 20 degrees total, 10 degrees per sidefor the faceform angle. One reason that face form angle becomesimportant is that when high corrections are placed into the prescriptionlens carrier, additional power would be produced in prescription lenses303 due to the face form angle. In other words, the prescription lenses,which contact the surface of lens 20, are angled relative to the face ofthe user. This effect could be corrected for by cutting a different lenscorrection properly altered for the angle. This would result in properperformance of the device. Alternately, a lens curvature may be designedto account for the faceform angle requirements. In one embodiment, alens curvature of 123.19 mm is included, which permits for a faceformangle of 10 degrees at the designed eye relief of 21.6 mm, while stillmeeting the optical and field of view requirements of the specificationand commercial specifications of ANSI. Z87.1. FIG. 4C shows parametersof one embodiment of lens 20. Other lens curvatures may be employedpreferably in the range of +/−5 mm of 123 mm. An illustrativeinter-pupilary distance (IPD) is illustratively shown as 64 mm.Pantascopic tilt (tilt angle relative to the face of the user) isillustratively depicted as zero in FIG. 4C.

Goggles tend to have pantascopic tilts of close to zero; howeverspectacle lenses tend to have much higher pantascopic tilts. Popularsports sunglasses have pantascopic tilts up to 15 degrees. Most of thedifference between these two devices is related to how they fit on thehead, making it more desirable to have higher pantascopic tilts withspectacles than goggles. This creates problems when trying to have acommon lens between both a goggle and a spectacle because of optical andlaser eye protection concerns. Varying the pantascopic tilts more than afew degrees either positive or negative will cause problems in meetingcritical optical and ANSI Z87.1 parameters such as prism and power.Certain technologies used in laser eye protection are limited in theamount of pantoscopic tilt that can be accommodated while stillretaining similar amounts of protection.

One embodiment of the present invention includes pantoscopic tilt oflens 20 at a nominal tilt of 3 degrees. The “as worn” design of thegoggle is set at 0 degrees, while the spectacle is set at 6 degrees forthis illustrative embodiment. Advantageously, this design permits for asingle lens design to be utilized between goggle and spectacle, whilestill meeting the optical and laser eye protection requirements.

Table 1 illustratively shows fields of view (FOV) with and without theprescription lens carrier (PLC) at a plurality of eye locations (45degree intervals). TABLE 1 FOV requirements Without Location (45increments) PLC (in degrees) With PLC (in degrees) Nasal 27 27 SuperiorNasal 32 32 Superior 32 32 Superior Temporal 54 38 Temporal 86 55Inferior Temporal 67 59 Inferior 37 37 Inferior Nasal 31 31The most difficult FOV requirements to meet are with the temporal andsuperior temporal regions. Users tend to wear either the goggle orspectacle closer to their eyes than the design eye location. Thisresults in an increased amount of FOV.

Advantageously, lens 20 includes a unitary design. No holes or slots areformed within the lens 20. In this way, stress risers anddiscontinuities, which can potentially compromise ballistic performance,are eliminated.

In preferred embodiments, lens 20 may include a composite of materiallayers to protect against different threats (e.g., wavelengths of light)and/or provide structural characteristics to lens 20 (e.g.,strength/ballistic resistance). In one embodiment, a single baseballistic lens 21 that passes ballistic requirements as a singlestand-alone device is included.

Lens 21 also serves as the foundation for attaching other technologies.For example, dielectric (DE) stacks 23 may be formed on a cap lens 25 asinorganic metal oxides. For example, dielectrics such as, titaniumoxide, silicon oxide, etc. may be employed. Cap lens 25 includes DEstack 23 formed thereon. DE stacks 23 include a plurality of layershaving different refractive indexes and being of thicknesses designed tocause interference of particular wavelengths of light. DE stack 23 maybe damaged in tension or during flexing. This is a particular concernwhen attaching DE stacks 23 to highly flexible polymers such aspolycarbonate. By attaching cap lens 25 to ballistic lens 21 a higherlevel of support is achieved thereby reducing the concerns for damagingDE stack 23 when formed on polymer materials such as polycarbonate. Lens21 and cap 25 are preferably made out of polycarbonate materials. Lens25 may also be made out of glass, with ballistic protection beingprovided by inner lens 21. Lens 21 may also include a hologram 27 orother layer to provide laser light protection, such as an organicdielectric stack or non-linear optical device. Hologram 27 may bestretched onto lens 21 by known processes. Lens 20 may include one orboth of DE stacks 23 and holograms 27. Lens 20 may simply include lens21 or any combination of items described herein.

The addition of cap 25 should not interfere with the attachmentmechanisms for the goggles (system 10) and spectacle (systems 100 and200 described below) lenses. Both the goggle and spectacle use differentmeans for attaching the lenses; therefore, these attachment areas shouldnot interfere with the line of sight of the user. Cap 25 may include anoptional anti-reflection coating (ARC) 33. ARC 33 may be provided on anylens surface described herein.

Referring to FIG. 6A, since lens 20 is secured at its periphery. Lens 20is interchangeable on a plurality of platforms. One such platformincludes, for example, a spectacle system 100. Spectacle system 100includes a frame 102. Arms 104 are pivotally connected to frame 102.Frame 102 includes extensions 106, which are configured and dimensionedto receive lens 20 therebetween. Extensions 106 form a groove 108 on aninternal edge such that when lens 20 is installed, lens 20 is capturedin groove 108. A support 110 is included which is mountable on frame102. Support 110 attaches to frame 102 in a way that permits somedeflection of support 110.

Referring to FIGS. 6B and 6C with continued reference to FIG. 6A,support 110 is capable of deflecting forward to accept lens 20. Oncelens 20 is installed, clips 112 on nosepiece 114 are secured againstlens 20 and clips 112 are preloaded against lens 20 to secure lens inspectacle frame 102 as a result of the deflection of support 110. Frame102 includes a brow bar 116, which is designed to provide the preload tosecure lens 20 with clips 112. Brow bar 116 is a flexible member capableof providing sufficient strength and flexibility to support ballisticsrequirements for system 100. For example, the spectacles of the presentinvention were subjected to a ballistic test in accordance withMIL-STD-662E using a 0.15 caliber, 5.8 grain, T37 shaped projectilefired at 640-660 feet per second (fps). The goggle and spectacle wereboth tested up to at least 700 fps and lens 20 was tested at speeds ashigh as 850 fps. The test required that at no time can the projectilecome through the device (e.g., lens 20) and break a witness platemounted on the inside of either the goggle or spectacle. In addition, nocomponents coming off of either device could penetrate this witnessplate as well. The designs described herein were designed to pass atleast this ballistics test.

In one embodiment, torsion is developed in support 110 by providing tabs118 integrally formed in brow bar 116. Tabs 118 are inclined relative tothe orientation of support 110 to provide an angular displacement ofsupport 110 in an unloaded state (e.g., no lens in FIG. 6B). Tabs 118are formed to engage holes 120 such that upon introducing lens 20 intospectacle 100 (FIG. 6C) and securing lens 20 with clips 112, support 110develops torsion in brow bar 116. This torsion is employed to securelens 20 in place. Tabs 118 are formed such that an angle is naturallyformed which represents a torsional deflection when support is rotatedto accept lens 20.

Clips 112 of nosepiece 114 may be installed by depressing clips 112toward each other (in the direction of arrows “C” and “D”) to get past anose arch portion of lens 20. Clips 112 are then released outward toengage and retain lens 20 within spectacle 100. Nosepiece 114 mayinclude a soft or elastomeric pad 122 to provide comfort for a user.Arms 104 may also include pads 124 to provide comfort for a user.

During ballistics testing, performed by the inventors, upon impact,spectacle system 100 oscillates. Such oscillations need to be damped toprevent collateral damage to a user. To increase the dampingcapabilities of spectacle system 100, the present invention employsflexible zones 126 between contact points (support 110 and arm 104).These flexible zones 126 contribute significantly to the damping ofoscillations through spectacle system 100. Frame 102 of spectacle system100 is formed using flexible materials, such as, for example,polycarbonate, polyamide (nylon) or polyester. Blends of these and othermaterials are also contemplated. Flexible zones 126 may be provided inbrow bar 116 by forming slots therein or reducing the cross-sectionalarea of brow bar 116. Advantageously, the oscillatory response ofspectacle system 100 can be determined and brow bar 116 may be designedsuch that damping effects are maximized.

A relationship between the geometry of brow bar 116 and the oscillatoryresponse has been determined using high-speed photography. When lens 20is hit with a projectile a very violent oscillatory response ensues.Surprisingly, a reduction in the rigidity of frame 102 improves theoscillatory response to a ballistic projectile despite the rigidityprovided to the structure by lens 20. If lens is held too tightly thematerial may be caused to break. By holding the lens less tightly, thelens is able to oscillate easier resulting in less energy beingtransmitted directly to the frame. Materials utilized for the frameincluded, for example, nylon and polycarbonate. Nylon, while a flexiblematerial, is not as good a material in impact as polycarbonate, whichhas more ductile material properties permitting the polycarbonate lensframe to more efficiently absorb impact forces. A reduction of thecross-sectional area in zones 126 of say, about 5% to about 80% may beemployed depending on the ballistic protection needed. This reduction ismeasured from the end portions of regions 126 to the center portion ofregions 126. The change in cross-sectional area is preferably graduallytransitioned to reduce stress. It is preferable that regions 126 includewell-radiused and blended tapers to reduce stress-risers in theseregions.

Referring to FIG. 7, an alternate embodiment of a spectacle systemincludes spectacle system 200. Spectacle system 200 includes a brow bar202, which is more rigid than brow bar 116 of system 100. A support 204includes clips 206 for brow bar 202 engagement and clips 208 for lens 20engagement. Support 204 includes a nosepiece 207 having opposing endportions 210 which can be compressed inwardly toward each other topermit lens 20 to pass over nosepiece 207 during installation. Uponrelease of compressed end portions 210, clips 208 secure lens 20 whilesimultaneously clipping lens 20 to brow bar 202 with clips 206 to securelens 20 in system 200.

Referring to FIGS. 8, 9A and 9B, support 35, support 110 and/or 204 maybe adapted to receive a prescription lens carrier 300. Lens carrier 300preferably includes snap-in features 304 for detachably fastening lenscarrier 300 to support 35, 110 or 204. Advantageously, lens carrier 300is attached to system 10 (or system 100 or system 200) at or over thenose of a user. In this way, a stable attachment point is provided sothat facial or body movements do not impact the position of lens carrier300. This is particularly useful for system 10 where goggles arestrapped to the head or to a helmet of a user and facial movementseffects the movement of goggles. By having an attachment point near thenose of the user, physical movements of the user have less impact on thealignment of lens carrier 300 with the eyes of the user.

Lens carrier 300 is adapted to receive prescription lenses 303 forindividual users. Lens carrier 300 preferably includes two protrusions304 or other mechanical features. Protrusions 304 are separated by alateral distance d to provide stability for lens carrier 300 relative tothe platform on which lens carrier 300 is mounted.

In one embodiment for system 10, for example, protrusions 304 eachinclude a bulbous portion 306. Protrusions 304 are compliant to permitthem to flex. In this way, protrusions 304 separate by a camming motionof portions 306 against grooves, which accept portions 308 in support 35during installation. (Portions 306 are shown in phantom lines in FIG.8A). Once past the depth of support 35, protrusions 304 unflex back totheir original position thereby locking lens carrier 300 in place. Lenscarrier 300 may be detached by pulling lens carrier 300 away fromsupport 35 to initiate the same camming motion during the removal oflens carrier 300.

In another embodiment for systems 100 and 200, for example, grooves 309are provided in support 110 or 204, bulbous portions 306 of protrusions304 are inserted into holes 310 and then slid along slots 312 to securelens carrier in place. (Portions 306 are shown in phantom lines in FIG.8B).

By providing a separate lens carrier, lens 20 does not need to providevision correction features. In addition, the design of systems 10, 100and 200 do not need to accommodate typical frames employed withcorrective lenses.

Lens carrier 300 may include flex zones 320 in a center portion topermit deflection and flexibility within lens carrier 300. While lenscarrier 300 has been shown and described in accordance with a specificembodiment, other attachment and detachment methods and structures arecontemplated by the present invention. It is preferable that thesestructures and methods include multiple laterally offset attachmentstructures to ensure stability of the lens carrier, and provide anattachment point at a stable portion of the system to which the lenscarrier is attached to permit facial and body movements of the userwithout interfering with the alignment between the prescription lensesand the users eyes.

The present invention provides for interchangeability of lens 20 betweenlens mounting platforms. Those skilled in the art understand thatgoggles and spectacles have different design requirements for lenses,which are mounted therein. Goggles typically include a greater stand-off(i.e., distance from the eyes of the user) than a spectacle. Therefore,goggles typically include a more planar shape than spectacles. Inaddition, spectacles provide more in the way of wrap-around protection.Thus, the spectacles typically form a more rounded or spherical shape.Since these designs include different requirements and shapes, oneskilled in the art would not be motivated to use a lens adapted for agoggles design with a spectacles and vice versa.

The present invention provides systems and lens designs which providefor interchangeability between goggles and spectacles while providingfor ballistic protection and low distortion of light through the lensfor both platforms. The completed lens assembly of the present inventionfits into both a goggle and a spectacle. Lenses of any type, forexample, clear, sunshade, laser protection, or other lenses fit in bothplatforms and are interchangeable therebetween. This was particularlychallenging since the goggles and spectacles are preferably employed formilitary applications. The goggles (e.g. system 10) preferably are a onesize-fits-all design. Field of view, lens tilt, and eye tolerancesneeded to be considered and maintained for proper eye alignment in thevarious platforms.

A sandwich or composite lens approach with multiple technologies presentis provided in accordance with the present invention. The lensconfiguration includes many advantages over prior art solutions.Holograms and DE stacks afford limited scratch resistance, and ifscratched, the laser protection would be completely lost in that area,rendering the item useless. It may take approximately a pico-secondexposure of a particular laser at a given strength to completely damagethe retina of a human eye. The holograms in particular are vulnerable toexposure to water vapor and weather. The holograms and dielectric stacksdegrade when exposed to some of the common battlefield chemicals andother materials (e.g., insect repellants, hydraulic fluids, differenttypes of fuels, and high concentration chlorine). The sandwichconstruction as shown in FIG. 5 for lens 20 includes two separate lenseswith holograms and dielectric stacks protected inside. The completedassembly fits in both a goggle and spectacle as described above for alllens types (e.g., clear, sunshade, laser).

Referring again to FIG. 5, lens 20 includes cap lens 25 and base lens 21which be treated with dyes on surfaces thereof or have dyes introducedinto the solid matrix or substrate of lenses 21 and/or 25. A dye(chromophore, absorber, colorant) may include a substance, which addscolor to substrates to which the dye is added (e.g., plastic, or glassfor lens 20). The dye may be introduced to absorb light in the visibleregion or other region of the electromagnetic radiation spectrum andthereby transmit and/or reflect colored light through/from the substratein which the dye resides. More broadly, a dye is any substance, whichabsorbs light in a region of the spectrum of interest to the observer.Thus, a specific dye may be introduced to absorb light in a specificband or bands in the electromagnetic spectrum (e.g., UV, VIS, NIR, IR,microwave, etc.) in accordance with the present invention.

In preferred embodiments, a dye or other compound may be introduced intolens 20 to absorb light in the visible, near infrared and/or ultravioletregions of the spectrum. The presence of the dye in the substrate may ormay not have coloration detectable to the human eye. Dyes employed inthe present invention may include organic compounds which are soluble inpolymers and which modulate the light passing therethrough. Such dyesmay include dyes from the families of metallo-porphyrins,metallo-phthalocyanines, aza-variants of these, annellated variants ofthese, squaryliums, croconiums, aminiums, diimoniums, cyanines, etc.Dyes may be selected and added to lens 20 for absorbing or filtering outspecific laser wavelength, UV radiation, NIR, IR or any visible light(e.g., sunshade). Dyes may be employed in lens 20 in combination tofilter multiple wavelength or bands of wavelengths, which wouldotherwise be permitted to pass through lens 20.

Dielectric stacks 23 may be included in lens 20 to further rejectwavelengths of light through destructive interference. When a wave frontof some characteristic wavelength encounters a sequentiation of baffles(each being a molecular/atomic/ionic species in some plane), the wavefront can be interfered with in a number of modes but most modes ofinterest are destructive (waves reflected from the front surface beingexactly out of phase with those reflected from the rear surface to givenegated waves).

If the front and rear surfaces are separated spatially by an oddintegral number of quarter wavelengths of the incoming wave in thedirection of the incoming wave, then interference can be expected. Whenapplied to light, and the “baffles” are a sequentiation of materials ofchosen thicknesses but which repetitively alternate in being one of highindex of refraction and one of low index of refraction, then theinterface between any two layers behaves as a mirror. If the thicknessof each layer is rigorously an odd integral number of quarterwavelengths of the incoming light, then the light will be interferedwith. Since some of the light gets transmitted through the “mirror” (itis not a perfect mirror), multiples of this first alternated layeringwill be needed to reject light of the given wavelength. Since the lightmay encounter the stack 23 at many different angles experiencing adifferent path of flight within that layer with each angle of incidence,then the layer thicknesses have to be appropriately altered insubsequent layers to account for nonorthogonal angular encounters whichare to be similarly interfered with.

If there is more that one wavelength which is to be interfered with,then additional layers are added for each wavelength to be considered.The end result is a large number of layers or stack to accommodateoff-angle hits up to some maximum angle, various wavelengths of light,and sequential identical layers to account for light leakage from onelayering to the next.

To construct dielectric stack 23 using a high refractive index materiallike SiO₂ and a low refractive index material like TiO₂ in such a way asto reject all wavelengths of light in the range from say the end of thevisible spectrum to from 680 nm to 1100 nm for all angles of incidencewithin say 50 degrees of normal incidence, then the resulting dielectricstack will be hundreds of layers thick and as a unit will be perhapsbetween 15 and 20 microns thick.

For reference, optical hard coatings placed on lenses for scratchresistance may be about 3 to 5 microns thick and are composed of aninorganic/organic polymeric mix called a polysiloxane. Adhesion of sameto an all organic lens surface like one of polycarbonate often takes useof primers and careful chemical processing to ease the transition of thechemistry of the all organic substrate to the organic/inorganic coating.Thus, with dielectric stack 23 which may be all inorganic to adhere toan all organic polymeric substrate, a similar transitional “primer” orsubcoating is used which again is a mix of organic and inorganicchemical moieties to bridge the drastic transition of the differingchemistries. Differences in moisture absorption, thermal coefficient ofexpansion, etc. often are the reasons why the inorganic stacks may failin delaminating from the organic substrate under environmental stressesof temperature changes, moisture, etc.

Although in theory such dielectric stacks can be deposited (most aredone best via high vacuum sputtering processes) so as to interfere lightof any wavelength, most success has been seen in achieving this in thered and near infrared portions of the spectrum and in doing so minimallyaffecting the visible region of the spectrum by not detracting fromdesired transmission of useful wavelengths of light.

Dielectric stack 23 may include a rugate. If in a sputtering process,where species of high and low indices of refraction are being depositedon a substrate sequentially in a dielectric stack, both species of highand low indices of refraction were deposited simultaneously but varyingsinusoidally with respect to each other's relative concentration, then arugate structure is formed. A rugate is a single thickness of mixedspecies (usually metal oxides) of high and low index of refractionwhereby the concentration of one oxide in the other oxide variessinusoidally in a very controlled fashion as a function of the depthinto the coating. If the sinusoidal variation were to be a true stepwave (tooth comb), then the rugate would be a layered dielectric stack.Rugates work in destructively interfering with light on the sameprinciples as described above where the periodicity of the concentrationvariation delivers the wavelength/angle rejection needed. While therugates can be constructed anywhere in the spectrum, most success todate have been at the blue end (low wavelength) of the visible spectrum.

Dielectric stack 23 may also include an organic dielectric stack.Organic dielectric stacks are analogous to inorganic dielectric stacks,but employ polymers of widely differing indices of refraction to replacethe metallic oxides of inorganic dielectric stacks. The polymer filmsinclude many layers, which can be laminated onto substrates by variousmeans. Polymethylmethacrylate may be employed, for example, as the highindex material and polyethylenenaphthenate the low index material in anorganic stack replacing, for example, the SiO₂ and TiO₂, respectively,of an inorganic stack.

Lens 20 may include one or more glass components (e.g., lenses). Glassis an inorganic polymer, which may include inorganic dyes to modify thespectrum of encountering and transmitted light much as organic polymersmay include organic dye molecules. Dyes for inorganic polymers mayinclude metallic ions (e.g., Fe⁺³, Cu⁺², Nd⁺³, etc.) along with theiranionic gegenions (oxide (O⁻²) being the most common). These dyes absorblight totally analogously to organic dyes but differ in two respects:(1) most metallic-ion dyes absorb rather broadly over spectral ranges asopposed to some organic dyes being narrow notch absorbers; (2) themetallic-ion dye absorptions extend farther out into the near infraredregion with less impact on the visible region than organic counterparts.

Lens 20 may include dyes, which produce a non-linear optical system.Nonlinear optical systems are different from linear optical systems. Forexample, in a linear optical system, an absorbing species (dye) absorbsincident electromagnetic radiation which is coincident with an energyexcitation from its ground state to its lowest excited state; thatabsorbed energy is then re-emitted quickly as light or via vibrationalcascades as heat or both.

Excitations and relaxations between electronic states of like spinsymmetry are the only ones which are not forbidden (i.e., which havenonzero probability of occurring). Transitions from singlet states willbe to other singlet states and from triplet states to other tripletstates. Spin state crossing is of such low probability that thosetransitions cause little more than low level noise in a spectrum. In anonlinear optical system, an absorbing species absorbs incidentelectromagnetic radiation into an electronic spin aligned excited state.However, the lifetime of the excited state is of such duration that theexcited state can cascade into an excited state of unaligned spin. Fromthat excited state, the state can then proceed to absorb radiation toexcite to spin aligned states from that excited state which are spinopposed to that of the initial ground state. These excitations, due toabsorptions of light by matter in excited states, produce a spectrum,which is totally different from that which would be generated if theintersystem spin crossing had not occurred. It is nonlinear in that partof the initial absorbed energy returns to the ground state and partcontinues on in a totally separate spectral life line. Dyes that producethe non-linear response may include fullerenes, and derivatives of thisfamily of compounds, for example.

Lens 20 may include a hologram(s) 27. Holograms are photographic images,which can be included internally to a coating or film and can belaminated to a lens. The image is not a classic image, but an image of aspectral region in which light will not be transmitted but reflected—aspectrally select partial mirror. This is effectuated by the film (adichromated gelatin or a photopolymer) in having its internal localindices of refraction altered by the laser light, which exposed it ingenerating the desired rejection mirror. The phenomenon is aninterference reflection phenomenon. Holograms are most successful in thelow wavelength region of the visible region of the spectrum. Hologramsare particularly useful in rejecting laser light at predeterminedwavelengths in the visible spectrum.

In one embodiment of the present invention, optical requirements formilitary eye protection systems were met as set forth in the ANSI Z87.1.The present invention is tested for many different requirements such aspower, prism, astigmatism, haze, distortion, and visual acuity. Both theunlaminated (clear and sunshade) and the laminated lenses met theserequirements.

With continued reference to FIG. 5, one aspect of the present inventionis to provide a zero power lens for ballistic protection. To make thelaminated (composite) lens 20 plano, the protective cap 25 had to havepower induced into it in order to make plano optics out of the assemblybecause lens 21 is also designed to be a stand-alone lens with planooptics. Cap 25 is shown in FIG. 5 with a portion removed (at the top ofthe cross-sectional view) to highlight the laminate structure. Power isinduced into the lens by carefully selecting the lens curvatures toinduce the proper amount of power into the lens assembly. Because thetwo lenses were being laminated together, the interface of these twolens surfaces is one important aspect of the present invention. Anindex-matching material 29 is used to minimize refraction caused by theadhesive layer. The surfaces should be closely index-matched as air gapsin between the lens surfaces can induce power and reduce the overalltransmission due to reflection. Unmatched surfaces will also reduce thelamination strength, as there is less contact area for the adhesive.Edges 41 (all around lens 20) are sealed with index-matched material 29,such as urethane for protection, if needed.

Therefore in accordance with the present invention, the curvature of cap25 relative to lens 21 is maintained to provide power such that theentire lens assembly 20 has substantially zero power and to maintainoptical density (transmission) through the lens assembly 20. Byproviding power to cap 25, index of refraction differences through lens20 are accounted for to reduce internal reflections, which reduce thetransmission of visible light through the lens 20.

In addition, curvature of the entire lens assembly 20, as a whole,provides interchangeability between goggles (system 10) and spectacles(systems 100 and 200) as illustrated in FIG. 10. To achieve this, lens20 provides sufficient wrap-around or side protection for spectacleswhile being planar enough to be employed in goggles. In addition, lens20 maintains an optical density, minimizes distortion, haze and otherdetrimental optical effects.

Light travels through solids slower then it does when traveling throughair. This, in tandem with a curved lens, causes the light to be bentcausing power to be induced through a lens. A plano lens has very littleoptical power (zero-power for cylinder or sphere lens) induced into thelens. This means to the human eye there is little difference betweenlooking through the lens (with the exception of reflected or absorbedlight reducing the transmission received to the eye) and the naked eye.With a spherical lens, zero-power is accomplished by varying the opticalcenters of a lens surface and varying the radius of the lens from thesecenters.

When a second lens element is added to a plano optic, if both of theselens designs were plano before being laminated, the resulting laminatewould have power induced to it due to the laminate structure. In otherwords, altering the overall thickness of the laminate structure ormaterial (i.e., density) or altering the radius of curvature of eitherlens results in power being induced into the laminate lens structure. Tocompensate for this effect, in accordance with the present invention,one or both of the lenses are designed with power so as to reflect thelight such that the resulting lens laminate still remains plano (e.g.,substantially zero power). This is more complex than just providing astand-alone plano device, because the cumulative effect needs to betaken into consideration.

Referring again to FIG. 5, in accordance with the present invention,depending on the particular configuration, lens 25 may be employed as acover lens and may not be needed for the lens assembly 20 (for example,if only ballistic protection is needed). In this instance, lens 21 is aballistic lens and is preferably of zero-power. In other instances, bothlens 21 and lens 25 may be used together.

Advantageously, the combination or sandwich of lenses is designed toalso have zero-power. In other words, lens 21 is zero-power alone, andthe lens assembly 20 as a whole is also zero-power. This may be providedby designing lens 25 to have non-zero power to compensate for any powereffects induced by employing the laminate structure of lens assembly 20.In alternate embodiments, the structure of lens 25 may include acombination of lenses. One of the lenses in the combination may includea duplicate of lens 21 and an additional lens (not shown) to form lens25. The additional lens would therefore include a radius of curvature,thickness and/or material to compensate for non-zero power throughoutthe entire lens assembly 20.

Therefore, assembly 20, when constructed, has substantially zero-powerwhen employed by a user. In this way, the lens assembly providesprotection to the user from one or more threats to ensure that littledifference exists between looking through the lens assembly (with theexception of reflected or absorbed light reducing the transmissionreceived to the eye) and the naked eye.

Zero-power lens structures are particularly useful in applications wheredepth perception must be maintained. For example, in military operationswhere the user must aim a weapon with eye gear on or spot a positionwith eye gear on, accuracy is important.

Although providing particular curvatures to the individual base lensesis difficult, initially in design, the product lens provided inaccordance with the present invention permits a high degree offlexibility. Ballistic lens 25 alone may be clear, tinted and mayinclude a dielectric stack having zero power, or lens assembly 20, whichincludes lens 25, may be employed with zero-power and provide laserprotection and/or other optical features as described above. Othercombinations of features and lens are also contemplated.

Haze can be a problem with holograms; therefore special care has beentaken by the inventors in the creation of the mold surfaces, curves andlens coatings to minimize the haze present in the base polycarbonatelenses. With careful attention to production processes the inventorshave been able to reduce the haze to less than 0.4%. Another problemwith the visibly reflective holograms is a problem called narcissus,which means the user sees the reflection of their eyes in the lenssurface. This is because the holograms reflect back certain wavelengthsin the visible spectrum. This problem may be solved using a small amountof organic absorber dyes, which provide a predetermined optical density(OD) to provide protection. Absorber dyes may includemetallo-porphyrins, metallo-phthalocyanines, aza-variants of these,annellated variants of these, squaryliums, croconiums, aminiums,diimoniums, cyanines, etc. (L-1 dye). Other suitable dyes may also beemployed. In one embodiment, the dye absorbs the reflected light andreduces the narcissus effect observed to acceptable levels. It alsohelps to provide protection against high angle incidence laser light asholograms only provide certain cones of protection and therefore arelimited on the available angular protection. Dyes may be added for otherpurposes as well. For example, a dye may be added to lens 20 to providesupport for a DE stack. The use of such dyes increase the adherence of aDE stack or other components formed on lens 20.

Therefore, the present invention includes lens and eye protectionsystems, which protect critical technologies from weather, chemicalexposure and scratching while permitting a stable and robust platformfor attachment of multiple laser protective technologies (DE stacks,holograms, organic absorber dyes, and polycarbonate (rugates, non-linearoptics and specialized glass lens materials may also be used in thisconstruct)). The lens is also capable of being worn and interchangedbetween a goggle and a spectacle and includes necessary optical,ballistic, field of view, transmissive/technologies.

One of the most difficult aspects for the present invention wasmaximizing the visible transmission of the device, while still providingnecessary levels of protection. The more visible light attenuated, themore undesirable the transmission is to the wearer. In one embodiment ofthe present invention, a laser lens (e.g., in lens 20) is included whichprotects against both tunable and agile laser systems in both thevisible and near infrared region of the electromagnetic spectrum. Thislens is a careful combination of various laser protective technologiesas described previously. The illustrative embodiment being describedprovides protection against over 400 nm of specific wavelengths of lightin these regions. The photopic transmission of this device exceeded 35%and exceeds 45% in other preferred embodiments. Note, a normal sunshadelens found in commercially available sunglasses has a photopic luminoustransmission of only 12-18%. Surprisingly, the laser lens createdprovides filtering protection three orders of magnitude greater than asunshade lens at the specific wavelengths required, while possessingtwice the photopic transmission, and still meeting ANSI Z87.1, ballisticand other important requirements described.

Having described preferred embodiments for eye protection systems (whichare intended to be illustrative and not limiting), it is noted thatmodifications and variations can be made by persons skilled in the artin light of the above teachings. It is therefore to be understood thatchanges may be made in the particular embodiments of the inventiondisclosed which are within the scope and spirit of the invention asoutlined by the appended claims. Having thus described the inventionwith the details and particularity required by the patent laws, what isclaimed and desired protected by Letters Patent is set forth in theappended claims.

1. A lens system for protection against laser light, and ballisticscomprising: a first polymer lens having a convex surface and a non-zeropower; two or more spectrally select filters, including a laser lightfilter; a second polymer lens having a concave surface; one of saidfilters comprising a dye disposed within one of the lenses; said filtersfurther comprising one or more laminates selectively disposed on saidconvex or concave surfaces; and an adhesive for adhering the lensestogether with the convex surface facing the concave surface toprotectively sandwich the one or more laminates therebetween and toprovide ballistics protection; wherein said second polymer lens having anon-zero power that compensates for power effects induced by the one ormore laminates, so that during use the lens system has a substantiallyzero power.
 2. The lens system as recited in claim 1, wherein said oneor more laminates comprise: a hologram disposed on said convex surface;and a dielectric stack disposed on said concave surface.
 3. The lenssystem as recited in claim 2, wherein said hologram provides protectionfrom laser light.
 4. The lens system as recited in claim 2, wherein thedielectric stack includes organic dielectrics.
 5. The lens system asrecited in claim 2, wherein the dielectric stack includes inorganicdielectrics.
 6. The lens system as recited in claim 2, wherein thedielectric stack includes a rugate structure.
 7. The lens system asrecited in claim 2, wherein the adhesive seals edges of the first lensand second lens to protect the hologram and the dielectric stack.
 8. Thelens system as recited in claim 1, wherein the first lens and the secondlens are formed from polycarbonate.
 9. The lens system as recited inclaim 1, wherein the laser light filter is selected from the groupconsisting of an absorber dye filter, an interference filter and areflection filter.
 10. The lens system as recited in claim 1, whereinphotopic transmission of the lens exceeds 35%.
 11. The lens system asrecited in claim 1, wherein the first lens provides ballisticprotection.
 12. The lens system as recited in claim 1, wherein the lenssystem provides ballistic protection in accordance with MIL-STD-662E.13. The lens system as recited in claim 1, wherein the adhesivecomprises an index-matching adhesive.
 14. The lens system as recited inclaim 12, wherein the adhesive seals edges of the first lens and secondlens to protect the laminate.
 15. The lens system as recited in claim 1,wherein the lens system includes a curvature such that the lens isinterchangeable and is mountable in both a spectacles assembly and agoggles assembly.
 16. The lens system as recited in claim 14, whereinthe curvature includes a radius of about 123 mm on a concave surface.17. The lens system as recited in claim 1, wherein the lens systemincludes two lobes for covering the eyes of a user and an arch formed inthe lens system between the two lobes corresponding to a nosepiece, thelens system being continuous without holes or slots.
 18. The lens systemas recited in claim 1, wherein the lens system includes a dye to preventreflections.
 19. The lens system as recited in claim 1, wherein the lenssystem is adapted to protect against at least one of ultraviolet lightand sunlight.
 20. The lens system as recited in claim 1, wherein thelens system includes a dye to provide a non-linear optical transmissionspectrum.
 21. The lens system as recited in claim 1, wherein at leastone of the first lens and the second lens is coated with an inorganicpolymer.